Homework 2 Cell Biology
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Cell Biology
Homework
NAME:
CLASS:
Homework 2 Cell Biology
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Cell Structure
1. The diagram below shows two cells.
a) Complete the table below to give the name and functions of the parts labelled A,
B and C.
(2)
Letter Part Function
A Cell Membrane
B Nucleus
C Site of chemical reactions
b) Which cell is a plant cell?
Cell
Reason
(2)
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2. Use the information in the table below to answer the questions about liquids used in
preparing microscope slides.
Type of cell Liquid Used Effect
Human cheek cell Methylene blue Nucleus turns blue
Onion epidermal cell Iodine solution Nucleus turns yellow
Human skin cell Eosin Cytoplasm turns pink
Onion root cell Acetic orcein Chromosomes turn red
a) Name two liquids used to prepare plant cells.
1
2 PS –Selecting (2)
b) What effect does eosin have on skin cells?
PS –Selecting (2)
3. Where is the genetic information found in animal and plant cells?
(1)
4. Which organelle is essential for photosynthesis in plants?
(1)
Total /10
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Homework 2 Cell Biology
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Enzymes And
The Use Of Enzymes In Industry
1. Complete the table below which shows the substrate and product of 2 enzymes
found in the small intestine.
Enzyme Substrate Product
Protein
Amylase
Maltose
(2)
2. Describe the properties of an enzyme which ensure each chemical reaction is
catalysed by a certain enzyme.
(3)
3. State what is meant by the term optimum when describing and enzyme reaction.
_____________________________________________________________________
___________________________________________________________________ (1)
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4. The diagram below show an enzyme and it’s substrate.
Add an arrow and label to the diagram to show where the active site is. (1)
5. The diagram below shows an investigation to compare the activity of catalase in
apple and liver.
ENZYME
SUBSTRATE
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a) State 2 variables not shown in the diagram that must be kept constant for a valid
comparison.
1
2 PS- Analysing (2)
b) Explain why enzyme activity decreases at temperatures above the optimum.
(1)
6. Liver contains the enzyme catalase. A piece of liver was added to hydrogen peroxide
and foam was produced as shown below.
a) Name the gas in the foam.
(1)
b) Which other product was formed during this reaction?
(1)
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c) Describe a suitable control experiment which could be used to show that active
catalase is needed for this experiment.
PS-analysing (1)
d) How could the activity of catalase be measured in this experiment?
(1)
Total /14
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Homework 2 Cell Biology
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Photosynthesis
1. Photosynthesis is the process by which green plants make glucose using energy from
the sun.
Name the by-product A released during photosynthesis.
(1)
2. What molecule is split during the first-stage of photosynthesis?
(1)
3. Hydrogen and a high energy molecule are produced during the first stage of
photosynthesis. Name the high energy molecule
(1)
4. Other than temperature, state two factors which limit the rate of photosynthesis.
1.
2. (2)
5. Describe the role of chlorophyll in photosynthesis
(1)
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6. What is the second stage of photosynthesis called?
(1)
7. On a cold winters day, plants will photosynthesise less. Why?
(1)
8. In the graph below, state the factors limiting the reaction at A AND at B.
A
B (2)
Total /10
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Temperature (oC)
Rat
e o
f p
ho
tosy
nth
esis
A
B
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Respiration
1. Cells need ATP for cell division. ATP is produced during the aerobic respiration of
glucose.
How many ATP molecules are produced per glucose molecule in this process?
(1)
2. Aerobic respiration occurs in two stages. Name both products of the first-stage, the
breakdown of glucose.
Product 1
Product 2 (2)
3. The following list contains some features of aerobic and anaerobic respiration in
germinating peas.
List
W Does not use oxygen
X Produces carbon dioxide
Y Yields 38 molecules of ATP per glucose molecule
Z Produced ethanol
Complete the table below by writing the letters from the list in the correct columns.
Each letter may be used once or more than once.
Aerobic respiration in germinating peas
Anaerobic respiration in germinating peas
(2)
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4. The graph below shows lactic acid concentration in blood during a period of vigorous
exercise (P) and of complete rest (Q).
Explain why lactic acid concentration changes during period Q.
(1)
5. What two substances are required by the cell to produce 1 moelcule of ATP?
1
2 (2)
6. Complete the word equation for aerobic respiration
GLUCOSE + + WATER + (3)
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7. What other name can be used instead of anaerobic respiration for the breakdown of
glucose in the absence of oxygen in plants and yeast cells?
(1)
8. Complete the summary table for aerobic and anaerobic respiration.
(3)
Total /15
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Aerobic
respiration
Anaerobic respiration in
animals plants and yeast
Glycolysis (y/n)
ATP yield
(number produced)
Product(s)
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Transport Across The Cell Membrane
1. Name the two molecules which the cell membrane is made of.
(1)
2. Which of the following molecules can both diffuse through a cell membrane?
A Amino acids and starch
B Amino acids and water
C Starch and protein
D Protein and water (1)
3. Most plant cells have a cell wall.
Name the structural carbohydrate in the cell wall.
(1)
4. Osmosis occurs in plant cells.
Name the substance that enters or leaves by osmosis.
(1)
5. The diagrams show the appearance of flower petal cells before and after being placed in solution X.
(a) What name is used to describe the appearance of the cells after being placed
in solution X? (1)
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(b) Describe solution X, with reference to its water content
(1)
(c) How could you return the cells to their appearance before?
(1)
6. One of the main functions of the lungs is the exchange of gases. Explain fully the
movement of oxygen and carbon dioxide in the lungs.
(3)
7. Draw a line to link the process and its description.
(2)
Total /12
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osmosis
diffusion
Active
transport
The movement of substances against
the concentration gradient which
requires energy.
The movement of molecules from an
area of high concentration to an area
of low concentration.
The movement of water across a
selectively permeable membrane.
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Use Of Enzymes and Microorganisms In Industries
1. State 2 different industries that use enzymes to make a product that is useful to man.
_________________________________
_________________________________ (2)
2. Describe how the enzymes are produced on a large scale for use in industries.
_____________________________________________________________________
_____________________________________________________________________
__________________________________________________________ (2)
3. State 3 conditions that are required for the growth of microorganisms.
1. ____________________________________
2. ____________________________________
3. ____________________________________ (3)
4. Which microorganisms is used in the production of yoghurt?
_______________________________________________________ (1)
5. Which microorganism is used in bread making?
_______________________________________________________ (1)
6. Which gas does this microorganism produce that results in bread rising?
_______________________________________________________ (1)
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7. Name the technique used when an experiment is carried out under sterile conditions
to prevent contamination of pure cultures of microorganisms.
(1)
8. Why would you need to allow a flamed loop to cool before using it to transfer a
sample of bacterial colony to a new agar plate?
(1)
9. Name 3 different conditions which must be controlled when growing cells in cell
culture
1
2
3 (3)
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10. The table below shows the results of an investigation into the removal of stains.
Type of Stain Washing
temperature (oC)
Biological detergent Non-biological
detergent
Grass 40
Mud 40
Grass 100
Mud 100
= stain removed = stain not removed
Grass stains were removed by a
A. biological detergent at 40 oC
B. biological detergent at 100 oC
C. non-biological detergent at 40 oC
D. non-biological detergent at 100 oC PS- Selecting (1)
11. Explain why using biological detergents is claimed to save energy.
_____________________________________________________________________
___________________________________________________________________ (1)
Total /17
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Homework 2 Cell Biology
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Homework 2 Cell Biology
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Producing New Cells
1. Cell division is also known as……..?
(1)
2. Stages of cell division are shown in their correct order in the diagrams below.
a) Add a label to show the spindle fibres on one of the diagrams. (1)
b) Refering to DNA, describe what has happened in the cell just before stage A
(2)
c) Stage C would be followed by stage D. Describe what would happen in stage D.
(1)
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3. Typical timings of the stages of mitosis are shown in the table below.
Stage A B C D Time (minutes) 88 33 25 54
What percentage of the total time for mitosis is taken by stage C?
% PS- Processing (1)
8. The diagrams below show 2 stages of mitosis.
Draw one straight line from each diagram to its correct description.
(2)
chromosomes shorten and thicken
chromatids are pulled to opposite
ends of the cell
chromosomes line up at the centre of
the cell
nuclear membrane reforms
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9. How does mitosis ensure that daughter cells will be able to function properly?
_____________________________________________________________________
__________________________________________________________________ (1)
10. What condition results from uncontrolled cell division?
_____________________________________________________ (1)
11. The table below shows the annual death rates from luncg cancer of ex-smokers who
had smoked for more than five years and then stopped smoking.
Time since ex-smokers stopped smoking
(years)
Annual deaths per 10000 of population
0 14
2 7
4 5
6 3
8 2
10 2
12 2
a) Draw a line graph of these results on the grid over the page.
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Time since ex-smokers stopped smoking (years)
PS- Processing (2)
b) The annual death rate from lung cancer for non-smokers is 1 per 10 000. What evidence in the table suggests that some of the damage caused by smoking for more than five years is permanent? _____________________________________________________________________
_____________________________________________________________________
_____________________________________________________________________
PS- Analysing (2)
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c) Underline one option in each bracket to complete the following sentences based on the data in the table.
rises The annual death rate from lung cancer for people who stop smoking stays the same falls
0 - 2 The greatest change is 2 – 4 years after. stopping. Within 8 years from stopping, 4 – 6 2 their risk of death from lung cancer is 7 times less than that of people who have 12 just stopped smoking.
PS- Processing (2)
Total /16
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Homework 2 Cell Biology
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Genetic Engineering
1. The diagram below summarises the steps in genetic engineering.
a) Identify cell type A ________________________________________ (1)
b) Name one product of genetic engineering.
__________________________________ (1)
c) Describe the advantages and disadvantages of genetic engineering.
________________________________________________________________
________________________________________________________________
________________________________________________________________
________________________________________________________________
________________________________________________________________
__________________________________________________________ (3)
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2. Insulin is used to treat people with diabetes. It can be manufactured by
genetically-engineered bacteria using the steps described below.
A Bacteria are grown in a fermenter and produce insulin.
B The human insulin gene is isolated.
C Plasmids are removed from bacteria.
D Human insulin is purified and used to treat people with diabetes.
E The human insulin gene is inserted into a plasmid.
F Altered plasmids are put into bacteria.
Arrange the steps into the correct order by putting the appropriate letter into each empty box.
(1)
B
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3. The diagram below shows stages in the production of a desired product by genetic engineering.
Identify structures X _____________________________ and
Y _____________________________
(2)
Total /8
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Homework 2 Cell Biology
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DNA and the Production of Proteins
1. The diagram below shows a yeast cell.
a) Name the structure shown in the yeast cell which
contains the genetic information.
________ ____________________________ (1)
b) Add an arrow and a label that points to this
structure. (1)
2. Complete the paragraph below using words from the word bank. Each word may be used once, more than once or not at all.
The building block of all organisms are ___________. The ______ __________of the
cell contains many thread-like structures called _____________________ which are
made of hundreds of smaller sections called _________ . Each of these
______________ control specific characteristics, such as eye colour, and are made of
a long chemical (arranged as a double helix) called __________ . Each strand of
_________ is made of repeating units called ___________ (e.g. ATGC). Proteins are
made of repeating units called __________ ____________ . The order of these is
controlled by the order of ______ on the DNA. (5)
Word Bank: Bases Nucleus Cells Genes Amino Acids
Chromosomes DNA
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3. Draw a line to match the bases in column 1 with their complimentary base in column
2.
Column 1 Column 2
A
C C
T G
T
(1)
4. All proteins are composed of A genes B DNA C amino acids D bases (1)
5. State 2 differences between DNA and RNA.
(2)
6. State the name of the organelle where proteins are assembled.
________________________________________________________ (1)
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7. Complete the following table of information on proteins and their functions.
Protein Group Function Example
Structural membrane proteins
Act as biological catalysts
to speed up chemical
reactions in cells
Hormones
Insulin
Provide specific defence
against body invaders
such as certain bacteria
and viruses
Immunoglobulins
Receptors Liver cells have receptors
for insulin
(5)
Total /17
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